Members of the British royal family have a flair for starting new trends. Queen Victoria popularized the white wedding dress, and more recently, Queen Elizabeth II made colorful hats look cool. Likewise, the bold wardrobe choices of Princess Margaret have not gone unnoticed. As Smithsonian reports, the gown she wore for her 21st birthday is now on display at London’s Victoria and Albert Museum.

The new exhibition is dedicated to the designs of Christian Dior, but one dress in particular became all the more notable after Princess Margaret wore it for her birthday in 1951. The cream-colored, off-the-shoulder ball gown is adorned with mother of pearl, beads, sequins, and raffia embroidery. When she saw it, Margaret jokingly remarked that the adornments resembled potato peelings. Still, she later described the gown as her “favorite dress of all.”

At the time, it was unusual for couture gowns to feature synthetic materials—especially a dress meant to be worn at a royal function. “This was a very modern choice in 1951 for a very modern princess,” Oriole Cullen, co-curator of the exhibit, told The Art Newspaper.

From Dior’s perspective, this was intentional. His collections ushered in a new era of opulence that marked a departure from the plain, no-frills fashions of the wartime years. Hundreds of other examples of Dior’s trendsetting styles spanning 71 years of the fashion house's history are on display at the exhibit, which is titled "Christian Dior: Designer of Dreams." A crimson-colored coat, a delicate silk tulle dress, and a larger-than-life embroidered dress adorned with Swarovski crystals are among the highlights.

As for Princess Margaret's dress: the materials made it something of a challenge to restore. Sections of the skirt had detached from the waistband and the beading had begun to come undone, but conservators at the museum did their best to make it look as good as new. "It was basically in remarkably good condition, but it bears a few stains which could not be removed without damaging the fabric," conservator Emily Austin told The Art Newspaper. "They are part of its history.”

The exhibit will remain on display until July 14, and tickets can be purchased online.

[h/t Smithsonian]